[SOLVED] I'm looking for HTC U11 601HT repair guide or schematics (free) - Phones & Tablets Forum

Hi,

I'm hoping you can help me out with my HTC U11 601HT. It's started acting up, and I'm looking for a detailed service manual with boardviews and schematics to properly diagnose and repair it. I need to take precise voltage measurements around the board, so having the right documentation would be very helpful.

Thanks in advance for your help.

Selected Answer

I actually found that service manual on a tech Discord server a while back. A really helpful member there shared a direct link to their blog and I've saved it. I'm happy to pass it along here. Hopefully, these boardviews and schematics help you fix your phone, just like they got me through my repair. Looks like we have the same model.

@Neil

Absolute legend! That's exactly the info I was searching for. This is going to save me so much time probing in the dark. Seriously, thanks a ton for sharing the link!

Hi there,

I also have the HTC U11 601HT and just downloaded the manual you shared. I'm pretty new to board-level phone repair, and this is a bit intimidating with all the tiny test points and the schematics. Could you point me in the right direction on how to start troubleshooting this ? Any advice on the first few things I should check would be a massive help.

Thanks so much for your time

General advices: start by checking the voltage at the battery connector on the board. With a known-good battery connected, you should see a steady voltage between 3.7V and 4.2V. After that, a great next step is to check the main power management IC (PMIC) for shorts. Using your multimeter in diode mode, check for shorts on the large input capacitors surrounding the PMIC.

Here are a few useful references for troubleshooting your device:
https://www.ifixit.com/Wiki/ASUS_X200CA_Troubleshooting
Take a look at comment #694
Also, this : https://www.ifixit.com/Guide/Xbox+One+S+Optical+Drive+Replacement/90204.
You can also check this video starting from minute 2:

The HTC U11 601HT service manual and boardviews from the link above were exactly what I've been searching for. I couldn't find a complete, free copy anywhere else. Seriously, thank you for sharing this you're a lifesaver!

Hi everyone, I'm working on a HTC U11 601HT with a no power issue and need some guidance with my measurements.
I'm detecting 3.3V on the VREG_MAIN line (pin 1 of the PMIC), which looks good, but I'm getting 0V on the VDD_CPU line (pin 8) where the schematics indicate I should see about 0.9V.
Since this is a core voltage for the application processor, could this missing rail be why the device shows no signs of life?
What's the best procedure to diagnose this further? Should I check for shorts on the CPU rail first, or look at the PMIC's enable signals?
I've already verified the main 3.3V and 1.8V power rails are present and stable.

My HTC U11 601HT was working perfectly until yesterday when it suddenly went completely dead. Now it won't respond to the power button, doesn't vibrate, and shows no signs of life even when connected to a charger. I'm worried there might be a serious issue.

I have a decent multimeter, a basic soldering iron, and a healthy dose of patience. While I've successfully replaced iPhone batteries and charging ports, this will be my first attempt at actual diagnosis. The sheer density of BGA chips and microscopic components is honestly a bit overwhelming.

I'm particularly curious about the alcohol trick I've seen online where you apply isopropyl to the board and look for evaporation hotspots to locate shorts. Is this actually a reliable method for beginners, or are there better approaches I should try first with just a multimeter?

I learned this lesson the hard way last month with mine, it was declared "dead" by two different shops. The phone showed absolutely no signs of life - no charging indicator, no vibration, nothing. Before diving into complex board work, I decided to try one more basic test: wireless charging.

To my complete surprise, it actually heated up on the charging pad! This single discovery completely changed my diagnostic path. It turned out the issue wasn't with the main board or processor, but with the notoriously fragile USB-C port that had failed completely. A $15 replacement part and some careful soldering brought it back to life.

The moral? Always exhaust every external testing method before opening the device. Test wireless charging if available, try different charging methods, and don't assume the worst case scenario. Sometimes the most "dead" devices have the simplest solutions hiding in plain sight.

I suspect my issue might be related to that cheap, third-party fast charger I used at the airport last week... Now the device gets extremely hot during charging, the screen flickers at low brightness, and sometimes it randomly shuts down at 30% battery. Could this have damaged the power management IC or battery calibration?

If your HTC U11 601HT starts acting up, random reboots, fast battery drain, or connectivity issues, there are several diagnostic steps you can take before assuming the worst:

• Check your charging habits: Using poor-quality chargers or wireless pads can gradually damage your battery and charging circuit, leading to unpredictable behavior.
• Inspect the physical components: A slightly damaged charging port, worn battery, or even accumulated pocket lint can cause issues that seem like major hardware failures.
• Monitor temperature patterns: If your phone gets unusually hot during specific tasks (like camera use or gaming), it could point to a failing component rather than a software issue.
• Use diagnostic tools wisely: Ampere for battery health, phone diagnostic codes (*#0*# on many models), and a thermal camera can reveal problems without opening the device.
• Know when to stop: If you see liquid damage indicators tripped or smell burnt electronics, it's time to consult a professional before causing irreversible damage.

Also visit this link it may help : https://xdaforums.com/t/contract-note-10.3969439/

Here's what I discovered on forums and technical databases:

With the proliferation of different charging standards (USB-C, Lightning, Micro-USB) and fast charging technologies (Power Delivery, Quick Charge), simply having a cable that "fits" is no longer enough. Hot Air Rework Station Method: Set your hot air station to an appropriate temperature (typically 300-350°C) and airflow. A crack in this frame compromises the phone's structural integrity and can lead to a cascade of other problems. Use the volume buttons to highlight "Reboot system now" and press the power button to select it. Fine-tipped Tweezers: For manipulating tiny parts and removing glass shards. Step-by-Step Repair Process (General Guide - Specifics Vary by Phone Model): Precise alignment is absolutely critical for proper sensor functionality. Improper Disassembly/Reassembly: This is by far the most common cause. As a last resort for software issues, a factory reset (after backing up data) can rule out deep software corruption. Overlap/Trim Corners: At corners, you can either butt two strips perfectly against each other or slightly overlap them and then carefully trim the excess with a sharp hobby knife for a clean finish. Faulty PA Signature: A failing PA often causes the phone to draw unusually high current spikes when trying to transmit, or it might show an unusually low, stable current where high fluctuations are expected, indicating the PA isn't engaging correctly. The replacement process is generally simpler than cleaning the sensor, as it involves removing the old module and installing a new, pre-assembled one. Final Continuity/Short Check: Verify the trace is continuous and there are no new shorts. Many Android phones have the charging port on a separate flex cable or a small daughterboard. If, after these assessments, significant and undesirable color shift is confirmed, especially after ruling out software settings, the issue is almost certainly a hardware problem with the OLED panel itself. This can be effective if a specific, hard-to-find setting or configuration is causing the problem. Apply a thin, even layer of no-clean liquid flux to the cleaned pads on the motherboard. Connect Battery Last: Ensure all other components are connected before re-connecting the battery. Contrast Detection Autofocus (CDAF): CDAF works by analyzing the contrast within the image. Slight variations can lead to compatibility issues or incorrect routing. Inspect and Clean: Before installing the new module, visually inspect the area where it sits for any dust or debris. Universal FRP Bypass Tools: There are numerous third-party tools (e.g., FRP Bypass Tool, GSM Flasher ADB Bypass FRP, SamFirm Tool, various "Miracle Box" or "Chimera Tool" type solutions) that claim to bypass FRP. "Calibration" for Face ID: In an Apple authorized service setting, this may involve proprietary tools to test the functionality and alignment of the Face ID module. They offer a lifeline for data recovery from otherwise irreparable devices and can, in rare cases, revive a phone with a faulty chip. In the intricate world of smartphone repair, precision is not just a virtue; it is a fundamental necessity. Remove the motherboard from the phone frame, disconnecting all flex cables, and place it on your anti-static mat. Look for any signs of physical damage, such as cracks on the RF ICs (Baseband PMU, RF transceiver, PAs), corrosion (especially after liquid damage), or missing tiny components (resistors, capacitors) around the RF section. Allow it to become tacky for a minute or two before placing the speaker. Charging Problems: Inconsistent or no charging, or the battery indicator behaving erratically. Gloves: Wear chemical-resistant gloves, preferably nitrile, to protect your skin from direct contact.

@Cristiane, Not sure what you're trying to say but ok :)